Nutritional StandardsGlycemic Index is based on a scale of 0 to 150.Low is within the range of 0-35,Medium is 36-70,High is 71-100,and Very High is over 100.The Glycemic index cannot be calculated, only measured in lab testing on humans.

Calories per Gram:A carbohydrate gram is 4 calories,a protein gram is 4,and a fat gram is 9.There is no standard for combined grams.

Zone Blocks:A carbohydrate block is 36 calories,a protein block is 28,and a fat block is 27.Combine one block of each nutrient to make a whole Zone block, which is 91 calories.